The hydraulic forklift truck hydraulic system makes a lot of noise when working, and the pressure fluctuates, causing unstable faults. The hydraulic system can be diagnosed from the following points.
1. The oil inlet of the forklift gear pump is not tightly sealed and air is entering;
2. The joint surface of the forklift gear pump is not tightly sealed and air is introduced;
3. There is insufficient oil in the forklift fuel tank or there are a large number of bubbles in the oil;
4. The small off road forklift oil filter is clogged or the oil temperature is low and the viscosity is too high, resulting in insufficient oil absorption and vaporization of the oil;
5. After changing the oil or replacing the hydraulic system parts, there will be a large amount of gas in the system, causing the return oil to contain a large number of bubbles but not completely disappear;
According to the experience of engineers from Xiamen Interquip Machinery Co., Ltd., we can refer to the following points to troubleshoot these faults.
1. During operation, use plastic film to check whether there is air leakage in the gear pump oil inlet pipe and joint surface. If there is air leakage, we should replace the oil inlet pipe and sealing ring;
2. Check the oil level in the fuel tank and refill it to the oil mark line;
3. Observe the color of the oil in the fuel tank. If it is milky white, it contains a lot of bubbles. Resting for a period of time can cause the gas in the oil tank to escape;
4. Clean or directly replace the forklift oil filter;
5. If there is a large amount of gas in the system, you can repeatedly operate the lifting, lowering, forward tilting, and backward tilting movements for a short period of time without load, so that the air in the system can be discharged to the fuel tank.
The above troubleshooting methods are for reference only. In order to more accurately diagnose and repair the cause of forklift failure, maintenance personnel should learn more and listen to the forklift driver's feedback and conduct on-site inspections of the forklift to fully understand the fault points of the forklift hydraulic system.